US 12,452,030 B2
Clock synchronization based on temporal photon bunching effect
Jianwei Lee, Singapore (SG); Lijiong Shen, Singapore (SG); Peng Kian Tan, Singapore (SG); and Christian Kurtsiefer, Singapore (SG)
Assigned to NATIONAL UNIVERSITY OF SINGAPORE, Singapore (SG)
Appl. No. 18/547,259
Filed by NATIONAL UNIVERSITY OF SINGAPORE, Singapore (SG)
PCT Filed Feb. 18, 2022, PCT No. PCT/SG2022/050074
§ 371(c)(1), (2) Date Aug. 21, 2023,
PCT Pub. No. WO2022/177507, PCT Pub. Date Aug. 25, 2022.
Claims priority of application No. 10202101741W (SG), filed on Feb. 22, 2021.
Prior Publication US 2024/0022391 A1, Jan. 18, 2024
Int. Cl. H04L 7/00 (2006.01)
CPC H04L 7/0075 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method of clock synchronization between first and second clocks on first and second ends, respectively, of an optical channel, the method comprising the steps of:
generating light exhibiting thermal photon statistics, as opposed to a Poissonian timing statistic of coherent laser light;
transmitting a portion of the light through the optical channel;
determining timing information of single photon detection events of photons of the light at the first side of the optical channel using the first clock and at the second side of the optical channel using the second clock;
using a temporal signature imprinted on the light as a result of the thermal photon statistics to identify temporal correlations between the single photon detection events at the first side of the optical channel and the single photon detection events at the second side of the optical channel; and
determining an offset between the first and second clocks based on the identified temporal correlations.